The present invention is directed to a method and to devices for adjusting a roller of a printing press. The roller is placed against another roller and a movable detent is used to hold it in place.
A device for adjusting a roller of an inking or dampening unit of a printing press, with respect to an adjoining roller, has become known from EP 0 826 501 A1.
DE 199 19 733 A1 discloses a device for setting the contact pressure between two rollers of a printing press. A spring force is applied to a first roller and it is fixed in place on a frame by an arresting device.
DE 197 19 305 A1 discloses a bearing arrangement for a roller of an inking or dampening unit. A roller holder can be positioned by use of a spring, and can be fixed in place by being clamped.
DE 42 32 163 C1 describes a device for maintaining a set positioning pressure of an inking roller by use of a temperature-dependent actuator.
EP 0 807 520 A2 shows a switching arrangement for printing cylinders with a double-acting work cylinder.
EP 0 653 302 A1 and DE 42 11 379 A1 disclose devices for adjusting a roller, wherein a work cylinder presses a roller against a mechanically displaceable detent.
The object of the present invention is directed to creating a method and devices for adjusting a roller of a printing press.
In accordance with the present invention, this object is attained by placing the roller against at least one other roller through the use of a positioning force. A detent, which limits the positioning path of the roller, is placed against the roller or a receiver of the roller. A motor can be used for displacing the detent. The motor or other operating device can apply two different forces acting on the roller, a first for production and a second for positioning.
The advantages which can be gained by the present invention consist, in particular, in the compact construction of the device. In this case, the diameter of each device is equal to or preferably less than the diameter of the cylindrical shell of the roller of the inking or dampening unit. For this reason, no hindrance between these devices will be a problem when several such devices are used next to each other, for example in the situation of two adjoining inking rollers with a riding roller placed thereupon as the third rollerxe2x80x94wherein all rollers are adjustable.
A preselectable positioning pressure of the inking or dampening unit roller is made dependably possible by utilization of a preselectable force that is generated, for example, by an operating device for linear movementxe2x80x94such as, for example, a motor for linear movements, i.e. a cylinder with a pistol; piezo-operating devices, electrochemical operating devices, etc.xe2x80x94gaseous or liquid media, or electrical current. This adjustment is reproducible, i.e. flattening of a rubber covering of a dampening or inking roller thus forming a roller strip. This means that the so-called xe2x80x9cinking or dampening roller stripsxe2x80x9d can be kept at a constant width by the flattening of a rubber covering of a dampening or inking roller.
It is not possible to affect a so-called xe2x80x9cchannel beatxe2x80x9d when the inking or dampening roller rolls over a gap on other rollers. The fixing pressure PF, and therefore the fixing force FF with which the roller journal of the inking or dampening roller is held in a fixed manner, can only be set to be larger by a multiple of the positioning pressure PA, and therefore also a multiple of the positioning force FA, with which the covering of the roller is pressed against the shell of an immediately adjoining cylinder or roller.
A rapid pre-adjustment of the rollers, also for compensating for changes in diameter in the course of production, and/or in case of changes in the Shore hardness of the rollers, is possible. Because of this the set-up times become negligibly small. It is also possible to adjust these rollers remotely, for example centrally from a press control console.
The receiver of the roller or rollers can be maintained xe2x80x9clocked inxe2x80x9d during the entire running time. A high degree of quiet running of the rollers is assured by this, even when the printing press is running, because the xe2x80x9cswing-upxe2x80x9d of vibrations at the roller journals/-shafts is not possible because of the application of a clamping effect or a blocking effect. By acting on the distributing cylinder with a fixing pressure PF, or a fixing force FF, which is/are greater by a multiple than the positioning pressure PA, or the positioning force FA, a detent, which follows the performed positioning, is pressed against a counter-bearing fixed in place on the frame so strongly that, with the prevailing operational state of the roller positioning, an unintentional movement of the positioned roller in, or opposite to the roller positioning direction E is impossible.